1. Field of the Invention
The invention relates to a control device for an internal combustion engine.
2. Description of Related Art
In Japanese Patent Application Publication No. 2001-248448, for example, an intake air cooling device that cools supplied air in two stages by using two cooling cores through which cooling water flows is disclosed. In this device, a first stage cooling core on an air supply upstream side on which a high cooling water temperature is set and a second stage cooling core on an air supply downstream side on which a low cooling water temperature is set form an integral combination built into an air supply manifold. According to this configuration, cooling water in a cylinder block is used as high-temperature water of the first stage cooling core, and thus a heat recovery amount increases and total efficiency is improved. In addition, the second stage cooling core, which is close to an air supply port, can cool blowback gas from a combustion chamber, and thus the occurrence of knocking is suppressed.
In a cooling device that has a configuration in which a high-temperature intercooler (hereinafter, referred to as an “HT intercooler”) through which high-temperature cooling water passing through a cylinder block flows and a low-temperature intercooler (hereinafter, referred to as an “LT intercooler”) through which cooling water adjusted to a low temperature by radiation flows abut against each other as in the related art described above, heat is transferred from the HT intercooler to the LT intercooler. Accordingly, the amount of heat transported from the HT intercooler to the LT intercooler might increase and the length of time required for engine warm-up might increase when, for example, radiation from the cooling water circulating through the LT intercooler to the atmosphere is performed during the warm-up of the internal combustion engine.